BCR/ABL rearrangement positive OR prior cytostatic treatment lasting > 7 days or prior treatment with cytostatic drugs other than vincristine, daunorubicin and prednisone OR prior severe illnesses which make treatment per the protocol impossible from the outset (BUT trisomy 21 is not an exclusion criterion) OR absence of the baseline data required for assignment to a risk group in accordance with the protocol (BUT patients for whom the MRD value could not be determined for technical reasons will be treated as protocol patients) OR the disease is a secondary malignancy or relapse OR death before the start of treatment